Title (fr)

Publication

Application

Priority

IB 9901204 W 19990628

US 11475098 A 19980713

Abstract (en)

[origin: WO0003474A2] A voltage converting multiplier circuit converts a single ended input voltage Vgain into a differential output voltage VOUT, and includes a differential input cell (120) and a differential output cell (130), each biased by a respective control current (140, 150). A control circuit includes an input device (R10) having a resistance Rin coupled to an input terminal (110), and a differential amplifier (A2) which controls the differential input cell to maintain a voltage at one end of the input device (R10) equal to a reference voltage VREF, so as to convert the input voltage into an input current dI equal to (VREF-VIN)/R1. A current mirror (160) ensures that the input current is splitted by the branches (123, 124) of the differential input cell (120), which current splitting is mirrored to the differential output cell (130). An output device (R14, R15) (having a resistance ROUT in each branch (134, 133) of the differential output cell (130) converts the differential output current to the differential output voltage VOUT, where VOUT = Vin(Rout/Rin)(Icout/Icin) where Icout and Icin are the control currents applied to the differential input and output cells, respectively. A temperature compensated voltage is achieved where Icin is a constant current and Icout is a temperature compensated current. A temperature compensated variable gain amplifier including the converter circuit is also disclosed.